Yes, Nokia 7 Plus does come with 18W fast charger in the box itself.
Yes, Nokia 7 Plus does have the OTG support.
No. Nokia 7 Plus does not have a dedicated memory card slot. It has a hybrid sim slot. So, you can use a MicroSD card and a sim card at one go.
No. Nokia 7 Plus does not support face unlock as of now. It is expected that Nokia will soon release an OTA update for it.
Great battery life, immersive display, solid design, and software at its purest, that's the Nokia 7 Plus for you.